How to reset PG Database on Heroku (for Rails app)?

heroku_pg_db_reset.md

It's important to note that running this reset will drop any existing data you have in the application

How to reset PG Database on Heroku?

• Step 1: heroku restart
• Step 2: heroku pg:reset DATABASE (no need to change the DATABASE)
• Step 3: heroku run rake db:migrate
• Step 4: heroku run rake db:seed (if you have seed)

One liner

heroku restart; heroku pg:reset DATABASE --confirm APP-NAME; heroku run rake db:migrate

Note 1

Heroku doesn't allow users from using rake db:reset, rake db:drop and rake db:create command. They only allow heroku pg:reset and rake db:migrate commands.

More info: https://devcenter.heroku.com/articles/rake

Note 2

If you have more than 1 remote, append --remote [your_remote_name] like this:

heroku run rake db:migrate --remote dev (dev is example remote here)

If you find yourself where you cannot re-run migrations as the code has changed since they were written you can do the following to reload the schema:

1. heroku pg:reset DATABASE
2. heroku run rails db:environment:set RAILS_ENV=production
3. heroku run DISABLE_DATABASE_ENVIRONMENT_CHECK=1 rails db:schema:load
4. heroku run rails db:seed

Step 2 is honestly new to me but from the limited reading it sets the DB's environment to production so I assume it knows the proper database.yml values to load. Either way it's required before step 3 will run and because it is a mutation operation on a prod env database you have to manually allow it via the ENV var.